My PC has been sitting for a bit (about almost a year) its not dusty i cleaned it all out with an air can, it worked last time i used it. It gets to the window emblem and shuts down, wont run in safe mode or anything. Its done this before i had to reformat, which isnt a problem i want to actually, but the problem is i dont have a disk of windows i have it on a flashdrive, will it work? without the pc even booting fully? iv never used a flash drive for booting windows before. I just dont want to do all the hooking up and stuff if flash drives wont work unless the pc boots fully and goes to the desktop. help please =) Thanks

Check the bios and see if you can select "boot from a USB external device". If you have this option, set it as the first boot device and insert the USB flash drive and reboot the computer